1. Field of the Invention
The present invention relates to industrial paint systems that spray workpieces with powdered paint.
2. Description of Related Art
Present manufacturing methods typically include a process for painting finished goods. For example, extruded metal parts are usually placed on racks and then passed before spray paint guns that paint the parts. The environmental concerns over the solvents in wet paint, has prompted many in the industry to use dry paint powder. Dry paint processes typically utilize paint guns that spray a dry electrostatically charged paint powder onto the parts. The workpieces are electrically grounded to attract and retain the powder. The powder covered workpieces are then passed through an oven that heats and flows the powder, so that the paint covers and is attached to the part. The extruded parts are typically quite long and are spaced apart 4-6 inches, such that a large amount of powder passes between the workpieces. In a typical assembly line thousands of parts are sprayed during each shift, resulting in the accumulation of a large amount of excess paint that settles throughout the paint area. The excess unused paint accounts for a significant cost in the painting process. It would therefore be desirable to have an apparatus that can collect and contain the excess powder so that the paint can be reused.
The paint powder is toxic, such that the existence of excess powder in the plant or workplace area creates a harmful working condition. The excess paint also tends to adhere to objects other than the workpieces. It would therefore be desirable to have an apparatus that would prevent the paint powder from circulating around the paint area and settling on structures other than the parts. When the paint color is to be changed, the excess powder must be removed from the paint area to insure that the old color powder does not mix with the new color powder. It would also be desirable to have an apparatus that would provide an easy method of changing paint colors.